查询词典 millimeter

Based on the combination of theory and practice, the scattering and leaky characteristics of various surface wave guide structure are systematically investigated, a set of design curves and optimal criterion are given, which have practical significance in millimeter-wave engineering.

从理论和实践的结合上对多种表面波导行结构的辐射和散射性进行了深入的研究，给出了一套在毫米波工程中有实用意义的设计曲线和优化判据。

In the last new years , as the demands of wireless communication system grows rapidly , the bands of microwave frequency had been saturated with various communication applications . To achieve wider spectrum for high-speed and high-capacity transmission , bands of millimeter-wave frequency are the solution of this problem . The advantage of MMW wireless communication systems is wider bandwidth comparing with microwave communication systems . To utilize the spectrum efficiently , many methods of complexly digital modulation is proposed . The more complex modulation , the higher linearity is required , and more various phase of signals are required to accomplish process of modulation . Therefore high-linearity and quadrature-phase modulator and demodulator are the emphasis of this thesis . For high level of integration , high performance and low cost , this chip is fabricated by the complementary oxide semi-conductor 0.13um process . A compact size of direct down-conversion and direct up conversion circuits will be presented in this thesis .

近年来随著无线通讯产业的蓬勃发展，微波频带已经趋近於饱和，为了追求更宽的频谱来达到更快传输速率及高资料容量的传输，宽频的毫米波频段提供了解决此问题的途径，毫米波无线通讯系统提供了相对於微波通讯系统宽频的优点，且为了更有效的使用频谱，各种不同且复杂的数位调变方式及方法被发表出来，越复杂的调变方式其所需的线性度越高，且需要更多不同的相位讯号来完成调变的过程，因此高线性度及四相位的调变及解调器将是此篇论文的研究重点，为了达到高整合性，高效能，及低成本的电路设计，我门利用互补式金氧半导体制程来完成此电路设计，因此一小面积的直接降频(Direct down-conversion)及直接升频(direct up-conversion)电路将在文中介绍。

The technology uses millimeter wave signals in the 28 GHz spectrum to transmit voice, video, and data signals within a three-mile to 10-mile radius.

这项无线技术使用 28 GHz 频谱内的毫米波信号在 3 米到10 米半径内传输语音、视频和数据信号。

The second figure "50" refers to the mouth of this telescope lens, to millimeter as a unit.

第二个数字&50&指的是这支望远镜的口物镜，以毫米为单位。

The key technologies of novel photoelectron elements to support RoF are optical generations and receivers technologies for millimeter wave subcarrier, including external modulator method, radio frequency up-conversion method, self-heterodyne method, generator of optical pulse self-modulation, and so on.

近年来，支撑RoF技术的新型光电子器件的关键技术有毫米波副载波光学产生技术和接收技术，其中包括外调制器方法、射频上转换法、光学外差法、毫米波调制光脉冲发生器等等。

Based on chirality electromagnetism theory, the models of intrinsic chirality and screw structure which making carbon nanotubes wave-absorption in millimeter to centimeter wave band has been presented.

根据手性电磁理论，碳纳米管的本征手性模型和螺旋结构模型会产生毫米波段或厘米波段的吸收。

GHz ridge－loaded helical groove slow wave structure with a 20kV electron beam are given and the investigations of the effect of the ridge dimensions and electron beam parameters on the small signal gain are carried out. It is indicated from the calculation results that this type of structure is suitable for use as s SWS of high power, high gain but narrow passband millimeter TWT, of which the 3dB gain bandwidth is 3.4%. In order to increase the bandwidth, the reduction of the ridge gap or the increase of the electron beam current in an allowable range may be useful.

GHz的脊棱加载慢波结构的具体尺寸，并对此结构中小信号增益随脊尺寸的变化情况及电子注参数对其影响进行了研究，计算结果表明：此结构适宜于作为高增益窄带毫米波大功率行波管的慢波线，其3dB增益带宽为3.4%，为了展宽其工作带宽，可以适当减小间隙宽度，也可在一定范围内提高电子注电流。

Because the THz is between the millimeter wave and the infrared, it is difficult to produce the THz radiation resonance. But the application such as the radars and far distance detecting need great power THz resource. The gyrotron is the only device who can produce great power THz wave.

由于THz波段处于毫米波与红外线之间，THz辐射的产生困难很大，目前THz源的输出功率大多在毫瓦数量级，对于雷达、远距离探测等重要应用，需要瓦级以上的大功率THz辐射源，回旋管是目前唯一可在THz波段实现大功率输出的器件，其输出功率可达千瓦量级。

This design topic is the design and manufacture process of thecompand type cast of metal mold for the high chromium white castiron milling of 80 millimeter diameter.

本次的设计题目是80mm高铬白口铸铁磨球金属型复合群铸模具设计及制造工艺。

Both the 38-millimeter case and stationary bezel are made of high-quality stainless steel, and a nylon band is accompanied by a durable buckle clasp.

无论是38毫米的情况下，固定挡板均采用高品质不锈钢，尼龙带，是伴随著持久的扣钩。

I'm not an actor. I'm a professor of paleontology.

我不是演员，我是古生物学教授

Spider Network Web site that is a very image of the name.

网络蜘蛛即Web Spider，是一个非常形象的名字。